Chief Delphi - Event Predictions

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Re: Event Predictions

Quote:

Originally Posted by PayneTrain (Post 1240200)

I've actually had a casual interest in FRC (I wasn't in FLL either) before I joined a team in 2008. I recall (can't cite the rule, that part of the game manual is lost in the FIRST website) there being a rule where the poof balls, the second most nonviolent game piece in the modern era (behind moon rocks) had a set velocity limit.

In a ranking of "lethalness" of FRC game pieces since 2003: 1st to 2008 trackballs and 2013 frisbees, 3rd to 2010 soccer balls, 4th to 2005 tetras, 5th to 2006 Poof balls and 2012 basketballs... taking into consideration the speeds produced by robots of that year during official matches...

I recall being hit several times by a bouncing/falling/flying trackball and being knocked aside or given severe whiplash from a hit to the head. That said, a nearly point-blank shot from our own shooter (or especially some of these ones capable of greater-than-full-court shots) could be exceptionally dangerous... Regardless, I consider either of these game pieces (or a fast-moving soccer ball or a falling tetra) to be far more harmful than the 2006 poof balls... which were the only ones that ever had a muzzle velocity cap!

I guess my point being that I think the GDC intentionally avoided muzzle velocity rules for these other more dangerous projectiles because of the situations in 2006.

Quote:

Originally Posted by PayneTrain (Post 1240200)

It's all fun and games until we get blood spilt on the field or in the stands by a game piece. Seriously. It would not be fun after that. FIRST would quickly become not fun.

I whole-heartedly agree... the potential for legal ramifications and/or injuries (particularly to people new to FIRST) is a very significant concern. It seems though, with the netting already in place it will be extremely uncommon for a frisbee from a robot to leave the field at high velocity...

Between the nets and field boundary, the lowest areas are the >6' walls above the feed stations. The barage of human-thrown "hammers" during the final 30 seconds resulted in very-fast moving discs coming through these gaps in large quantities (and being very dangerous!), with others clearing the high goals or nets. However, the robots are almost exclusively shooting discs with horizontal-style throws... these slow down more quickly... and slow faster the steeper they're shot! This means that for shots to clear even these lowest points, they must be shot fairly steeply (and so slowing quickly) or are quite a distance from their fastest point. I expect robots to be accidentally shooting discs out of the field; however, I wouldn't expect these to present as significant a threat as some have been saying...

That said, shooting in the practice field or pits will be as dangerous as the teams shooting make it... Everyone in these areas needs to be very safe about if/how they shoot and bystanders should be aware.

I guess in summary, I don't think FIRST should apply a muzzle velocity requirement... partially to avoid any potential double-standards and partially because the in-match scenarious aren't the most dangerous ones. It seems to me that with the safety measures already in place the risks around the official field won't be excessive. Teams must be warned firmly, though, to be very careful with any shooting in the practice field (or pits... although it seems like requiring immediate arrest of shots would be sufficient for the pits).

Re: Event Predictions

Quote:

Originally Posted by 1075guy (Post 1240219)

Really, just net the alliance station walls too. Problem solved. You dont need ceiling access to the venue, just build the alliance walls so that the end uprights have a 10+ft vertical extension to hold a net across.

At the "Week Zero Scrimmage" in Nashua, NH with the official FIRST field, there were nets set up at either end of the field, in addition to the side nets.

I can't remember exactly where these were, but I believe they were placed just behind the back of the driver station / human player area. In other words, frisbees would be prevented from going out into the stands. I can't recall just how high they were, but I think they were the same height as the ones at the sides of the field. With that additional netting, I think FIRST has done a pretty good job of containing frisbees.

I don't remember if close-range shooters (thus steep angles) making high velocity shots that missed the top goal were going over the top of the net or not. I'm sure the people working field reset would remember, though!

In all honesty, I think the only big problem with frisbees escaping from the field were the human player throws in the last 30 seconds (the "blizzard") which has been largely addressed with the rule update making such throws valid only with colored discs, limiting the quantity of such throws and thus encouraging better accuracy from human players, rather than having them simply try to get rid of as many as 30-50 left over frisbees in 30 seconds. (At the Week Zero tournament, there were often many, many frisbees left over, since the robots were still frequently incomplete or only partly functional.)

Re: Event Predictions

Quote:

Originally Posted by IKE (Post 1239567)

You should be fine in the pits since safety glasses are mandatory. ::safety::

But safety glasses protect one thing and one thing only... your eyes.

Re: Event Predictions

Quote:

Originally Posted by thefro526 (Post 1240220)

You're right, there was a velocity limit in 2006, but I can't remember exactly what it was. IIRC, it was phrased as both a speed (XX distance/time) and a real world spot checking value (Shot at X trajectory should not go further than Y reference point), which made it pretty useful.

you don't have the 2006 rules saved on your computer? ;)

Code:

<S02>  Muzzle Velocity - No ROBOT may throw a ball 

with an exit velocity of greater than 12 m/s (26.8 mph). As 

a reference, a ball traveling at this velocity when leaving 

the ROBOT at an angle of 30º from horizontal with no spin 

will travel approximately 35 feet. A robot that violates this 

rule will be considered unsafe per <S01>.

Re: Event Predictions

Quote:

Originally Posted by MrForbes (Post 1240316)

you don't have the 2006 rules saved on your computer? ;)

Code:

<S02>  Muzzle Velocity - No ROBOT may throw a ball 

with an exit velocity of greater than 12 m/s (26.8 mph). As 

a reference, a ball traveling at this velocity when leaving 

the ROBOT at an angle of 30º from horizontal with no spin 

will travel approximately 35 feet. A robot that violates this 

rule will be considered unsafe per <S01>.

I'm still not sure this rule was as much for safety as it was for game mechanics. With out this rule 2006 would have been a very different game. Full court shooters in 2006 would have completely broken the game.

Re: Event Predictions

I have a serious question.
Concerning the Gray 8" Pneumatic wheels.

I keep seeing post after post after post about, "You shouldn't be using those...they are "unsafe." While I grasp the concept that spinning those dinky gray wheels at 4000+rpm could compromise their integrity. However, To make a full-court shot from our shooter with two wheels it takes less than 2500rpm and you're already goingto be overshooting the goal by a bit....so why on earth are you sayying someone is spinning their shooter at 4000+ rpm. I realize teams are using those bag motors that spin at 14000rpm....but seriously is this actually happening...?
I'd also like to see the concrete data on the tolerances of the wheel ...now I honestly don't know where that information is...neither have I searched for it.

In either case...Our team did take a precaution of mounting a bulletproof lexan/polycarbonate box around our shooter wheels. So if something did go horribly wrong...no one is going to have anything to worry about.

I'd also like to point out that the plaction wheels fronmandymark have an even greater change of having the non-slip (orange) material fly off...I know it does because the first shooter I tested had it break off in less than an hour.

Re: Event Predictions

Frisbees can hurt quite a bit, and I'm glad to hear about the netting behind the drivers stations. Keep safe, everyone!

Re: Event Predictions

I predict everyone is getting too worked up about this. Yeah, robots are going to fall off the pyramid. But if this permanently damages your robot, that's too bad, should've built a tougher bot. I'm sure at some point, someone will get hit with a Frisbee, but unless it is at point blank range, they will walk away from it. Seems like a few people need to go sit behind the dugout at a major league baseball game. ;-)

Re: Event Predictions

Quote:

Originally Posted by catacon (Post 1240486)

Since I've seen unconscious spectators removed on stretchers from baseball and hockey games, you're not helping my comfort level. I'll feel bad if ANY teams' robot falls from their pyramid, but that's their choice to try to climb. It's a choice to be a spectator, too, but a frisbee to the head causes a different kind of damage.

GKC's queuing areas are right where frisbees coming over the drivers' stations will be landing...it's not just spectators. I've been to other regionals with similar layouts; those side nets aren't going to protect everyone.

Re: Event Predictions

I can vouch for the fact that the frisbees hurt and not matter how safe we are you can get hit if you are not aware they are coming at you. The team was running tests and underestimated the power of the shooter and one got me in the hand. My finger was bruised and swollen for a few days. It wasn't pretty and it only grazed me. I can only imagine what ones of these guys could do to the head of some random person spectating who loses focus for a moment. I hope everyone is safe this year.

Quote:

Originally Posted by kiasam111 (Post 1240430)

Frisbees can hurt quite a bit, and I'm glad to hear about the netting behind the drivers stations. Keep safe, everyone!

Re: Event Predictions

Quote:

Originally Posted by pyroslev (Post 1240300)

And I've taken a Frisbee to the head down. They hurt but as long as you don't catch one in the throat within the first 10 feet or so, I don't think we'll see decapitations.

Color me relieved...

Re: Event Predictions

Quote:

Originally Posted by catacon (Post 1240486)

Well I'm glad that you can dismiss the concern. But I don't care to have my head split open and attending eight events tend to increase my odds of that happening. So I think I will continue to harbor my concerns thank you.

Re: Event Predictions

Really not sure what worries me more. Getting hit by a 1/4oz wheel weight ejected from a shooter wheel at thousands of rpm, or getting hit by a frisbee. Certainly the frisbee will be more common, but those little wheel weights will be like bullets if they leave your shooter.

Re: Event Predictions

Quote:

Originally Posted by 1075guy (Post 1240559)

I thought FIRST mandated that all moving parts had to be shielded in the robot.

Re: Event Predictions

Quote:

Originally Posted by 1075guy (Post 1240559)

Would not be surprised to see First implement a shooter wheel safety check in the queue to spot unsafe wheel balancing....